NEW YORK – If fall’s gray palette seems a bit depressing, get ready for a dose of fashion Prozac.

The spring collections shown at New York Fashion Week were full of optimism, featuring bright colors and bursts of gold. Donna Karan showed a graffiti print in hot pink for her DKNY line on Sunday, while Michael Kors took on a disco theme.

Kors’ collection featured sunny gold, as did those of Proenza Schouler and Ralph Lauren – the toast of one of the week’s highlights, his 40th anniversary celebration on Saturday.

Throughout the week, there’s been hardly a hint of black, if you ignore the audience.

New York Fashion Week lasts eight days, previewing the spring-summer looks of 100 or so designers for fashion editors, retail buyers and stylists.

MICHAEL KORS

An explosion of color rocked the tents at New York Fashion Week with Michael Kors’ spring collection.

For all the lovely dainty dresses that retailers, fashion editors and stylists have seen at Bryant Park over the first half of Fashion Week, Kors offered the opposite in splashy and sunny clothes, ranging from a form-fitting rainbow color-blocked sweaterdress to a floral ruffle bikini in a print done in the spirit of the artist Seurat.

The audience, which included Jessica Simpson, got into the joyous spirit of the show when a glittery pink dress came down the runway to the soundtrack of “Xanadu.”

He didn’t forget, though, that his fans also depend on him for their daily dose of luxury. He delivered that with a gold brocade tunic and a black-crystal jersey jumpsuit with a halter top.

Avril Graham, executive fashion editor at Harper’s Bazaar, called it “Charlie’s Angels meets Greenwich country club.”

DKNY

Mix it up. That was the message Donna Karan conveyed as she presented her spring DKNY collection at her downtown studio.

Outfits alternated between crisp white tailored looks, including a coatdress with a portrait collar, and soft stretch cotton T-shirt styles. A navy-and-orange striped dress from the latter group would have been the perfect thing to wear on an Indian summer weekend day: It takes the wearer from brunch to the bookstore.

DKNY is Karan’s more casual, contemporary line, and for this cool customer, there were the long, loose sundresses that editors, retailers and stylists have grown accustomed to seeing at New York Fashion Week.

Karan also continued with the color-blocking trend – a shift dress and a swinging coat (not worn together) in a navy, steel and orange combination was still fresh looking, though.

She also embraced a bit of a peasant look with some of the dresses and blouses, with flowing bodices, off-the-shoulder necklines and bell sleeves, but the prints she used had a hint of graffiti to them.

PETER SOM

Peter Som turned out a collection of classic American sportswear, offering chic daytime dresses with full skirts, metallic eveningwear and even tweed.

The tweed, though, looked appropriately light for spring, not like its cozy fall cousin. It was a mix of bright colors that he called “pixel,” and the best look of the group was actually a silk chiffon dress with horizontal pleats on the top and vertical ones on the bottom.

Som also had a group of blush pink and ice blue outfits that were mostly dressy cocktail-party looks. The highlights were a sparkling stadium coat with the pink used for two stripes at the hem and a dress that had sheer fabric pleats covering a metallic pink sheath.

“He’s someone everyone has had their eye on for a while,” said Kate Betts, editor in chief of Time Life + Style. “But what had been missing up until now is a commitment to American design. He had a European moment there for a while, but I think this is what’s right for him.”

Som likely will continue on this patriotic path: He recently was named the creative director for legendary design house Bill Blass, which made its name with sophisticated sportswear.

ALICE TEMPERLEY

The runway turned into a boardwalk at Alice Temperley’s fashion show Saturday, inspired by the French seaside and the freedoms women enjoyed during the 1920s, demonstrated through their fun and frivolous bathing costumes.

There was a lightness to the clothes that captured a playful spirit for an audience that included Demi Moore, Christy Turlington and Molly Sims. Many daytime dresses had tiered skirts, and one particularly nice dress was a white-and-black feather print with a loose braided halter.

For evening, Temperley offered a coral-colored gown with all-over pintucks, including a diamond pattern on the bodice, a black-and-white knit dress with a scalloped hem, and a white strapless dress with a black scroll pattern on top and long black stripes on bottom.

But what’s up with the rompers – sort of short jumpsuits? Not to pick on Temperley, hers were no better nor worse than the dozen or so others that have been spotted on the runways.

Maybe it’s because many of the designers have cited both the ’20s and the beach as strong influencers for the season, but rompers are likely to be a hard sell with a woman in 2008.